L20 - Restrictive Thoracic Disorders Flashcards
Definition of restrictive thoracic disorders
- Lung volumes (TLC) is (reduced/increased/preserved)
- Airway resistance and expiratory air flow are (reduced/increased/preserved)
- How is TLC and RV measured?
- reduced
- preserved (normal FEV1)
- Whole body plethysmograph (aka body box) or helium gas dilution
List the 4 general categories of restrictive thoracic disorders
- Pleural
- Interstitial
- Neuromuscular
- Thoracic/Extrathoracic
Pleural effusions, pneumothorax, asbestosis disrupt mechanical function that leads to shortness of breath +/- pain are examples of what category of restrictive thoracic disorders?
Pleural
Idiopathic pulmonary fibrosis, Vasculitis, Sarcoidosis, Asbestosis are examples of what category of restrictive thoracic disorders?
Interstitial
Myasthenia Gravis, Myopathy, ALS are examples of what category of restrictive thoracic disorders?
Neuromuscular
Obesity, Kyphoscoliosis, Massive ascites are examples of what category of restrictive thoracic disorders?
Thoracic/Extrathoracic
- This structure is a continuous mesothelial surface enclosing a potential space that is 10-20 µm in width
- Parietal blood supply is from ________
- Visceral blood supply is from _______
- Innervation is from parietal pain fibers in the costal surface via ________ and diaphragmatic surface via __________
- Pleura
- intercostal aa
- bronchial aa
- intercostal nn and phrenic nn
Which nerve can result in referred pleuritic pain to chest wall and shoulder?
Phrenic nerve
T/F visceral pleura has pain fibers
FALSE - no pain fibers
Which is FALSE regarding pleural physiology?
A. Normal pleural space has greater than 5 ml of fluid
B. ~500 ml of fluid secreted and drained daily through lymphatics
C. Pleural pressure negative at functional residual capacity
• -5 cm H20 at FRC
• more negative on inspiration
• positive with active exhalation (exhalation usually passive)
A. Normal pleural space has less than 5 ml of fluid
volume of air present in the lungs at the end of passive exhalation
FRC (functional residual capacity)
- (Transudation/Exudation) is when pleural fluid accumulates due to changes in hydrostatic forces (Starling forces)
- There is (decreased/increased) capillary filtration pressure due to vol overload (renal failure) or LA HTN (CHF)
- There is (decreased/increased) plasma oncotic pressure) - due to cirrhosis or nephrotic syndrome
- Transudation
- increased
- decreased
- (Transudation/Exudation) is when pleural fluid accumulates due to increased leak across capillaries
- List the 3 “I’s” associated with this process
- Exudation
2. infection (pneumonia); inflammation (RA, SLE); infiltration (metastatic cancer)
- (increased/decreased) flow through lymphatic stroma can cause pleural fluid accumulation
- List the 3 “I’s” associated with this process
- decreased
2. infectious debris (pneumonia, empyema); inflammation (radiation fibrosis, old injury); infiltration or tumor
The most likely cause of pleural fluid accumulation is a combination of (increased/decreased) fluid influx and (increased/decreased) lymphatic clearance
- increased
2. decreased
Pleural Effusion Transudation vs. Exudation
• increased filtration pressures and/or decreased oncotic pressures
• protein poor (not actively secreted fluid), low cell counts
Transudate
Pleural Effusion Transudation vs. Exudation
• increased capillary leak and/or decreased lymphatic clearance
• protein rich, cellular
Exudates
3 Symptoms of pleural effusion
- Dyspnea
- Chest pain (if parietal pleura inflamed)
- Asymptomatic
Pleural Effusion exam findings (3)
- Percussion dullness (if large)
- Absent breath sounds
- Egophony at top of effusion
A. CXR of pleural effusions show what 2 main features?
B. What do you see on lateral decubitus view?
A
1. loss of phrenic angles (high hemidiaphragm)
2. density with meniscus
B. free flowing effusion layers
Which is false regarding thoracentesis?
A. Aspiration of fluid from pleural space
B. Indicated in all new infusions except very small effusions or CHF effusions
C. Risks: bleeding, infection, pneumothorax
D. Avoid neurovascular bundle under rib
• So needle INFERIOR to the rib
D. Put needle superior to the rib
Pleural Effusion LIGHT’s Criteria defines an exudate as any one of the following:
- Ratio of pleural fluid /serum total protein of greater than _______
- Ratio of pleural fluid /serum LDH of greater than ______
- Pleural fluid LDH greater than ____ upper limit of normal serum LDH
1.greater than 0.5
2. greater than 0.6
3. greater than 2/3 upper limit of normal serum LDH
• If none of these criteria are met, then it’s a transudate
Requires no further invasive evaluation
Treat underlying disease (e.g. diuretics, dialysis, etc)
Which has a more extensive ddx, transudative or exudative pleural effusion?
Exudative
infections, neoplasm, PE, connective tissue disorders, post cardiac injury (dressler’s synd), asbestos-related effusions, GI disorders, uremic pleuritis, Meig’s syndrome, Yellow-nail syndrome, chylothorax, trapped lung
What is this condition? • Symptoms: • Sudden onset Chest pain • Dyspnea • Exam: • Often none • Percussion hyper-resonance • Absent breath sounds • X-ray: • Hyperlucency • Loss of lung markings • Peripheral pleural line
Pneumothorax Air in the pleural space